|I purchased onion sets from The Home Depot. When it rains, I have worms on the ground in my onion patch. They are not native to my location in northern Wisconsin, as nooone here knows what they are, and I am a Horticultural Specialist for store #4930. The worms are segmented and about four to six inches long. They are about 1 to 2 millimeters in length. On all the worms, the color is yellow,|
|I can't tell from your description, but cutworms, armyworms, onion maggots, and wireworms are insects that feed on onions. The Univeristy of Wisconsin may be able to identify the pest for you. Here's their publication on onion maggots. Maybe this will help.